Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Long-term Debt, Unclassified [Abstract]
Credit Facility	$ 406,103	$ 495,993
Term Loans:
Costis Maritime Corporation and Christos Maritime Corporation	0	82,500
Mas Shipping Co	22,375	30,625
Montes Shipping Co and Kelsen Shipping Co	54,000	66,000
Capetanissa Maritime Corporation	0	45,000
Rena Maritime Corporation	0	42,500
Costamare Inc.	50,313	60,463
Costamare Inc.	0	111,417
Undine Shipping Co., Quentin Shipping Co. and Sander Shipping Co.	178,264	193,545
Raymond Shipping Co. and Terance Shipping Co.	115,964	126,878
Costamare Inc.	53,475	68,170
Uriza Shipping S.A.	36,833	0
Costis Maritime Corporation, Christos Maritime Corporation and Capetanissa Maritime Corporation	109,000	0
Rena Maritime Corporation, Finch Shipping Co. and Joyner Carriers S.A.	32,000	0
Total Term Loans	652,224	827,098
Total	1,058,327	1,323,091
Less: Deferred financing costs	(3,720)	(4,499)
Total long term debt, net	1,054,607	1,318,592
Less: Long-term debt current portion	(199,637)	(185,259)
Add: Deferred financing costs, current portion	1,360	1,431
Total long term debt, non-current, net	$ 856,330	$ 1,134,764

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- Definition

Custom Element

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- Definition

Including current and noncurrent portions, aggregate carrying amount of the Credit Facility as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Including the total current and noncurrent portions, aggregate carrying amount of the Term Loans as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Including current and noncurrent portions, aggregate carrying amount of Capetanissa Maritime Corporation term loan as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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No definition available.

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Including current and noncurrent portions, aggregate carrying amount of Costis Maritime Corporation and Christos Maritime Corporation term loan as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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No definition available.

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Including current and noncurrent portions, aggregate carrying amount of Mas Shipping Co term loan as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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No definition available.

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Including current and noncurrent portions, aggregate carrying amount of Montes Shipping Co and Kelsen Shipping Co term loan as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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No definition available.

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Including current and noncurrent portions, aggregate carrying amount of Costamare Inc. term loan (Msc Romanos, Msc Methoni, Msc Ulsan, Koroni and Kyparissia) as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Including current and noncurrent portions, aggregate carrying amount of Costamare Inc. term loan (eleven vessels) as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Including current and noncurrent portions, aggregate carrying amount of Costamare Inc. term loan (Hulls S4010,S4011) as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Including current and noncurrent portions, aggregate carrying amount of Raymond Shipping Co. and Terance Shipping Co. term loan as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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No definition available.

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Including current and noncurrent portions, aggregate carrying amount of Rena Maritime Corporation term loan as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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No definition available.

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Including current and noncurrent portions, aggregate carrying amount of Undine Shipping Co., Quentin Shipping Co. and Sander Shipping Co. term loan as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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No definition available.

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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- Definition

Amount, before accumulated amortization, of debt issuance costs classified as current. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt classified as other, payable within one year or the operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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